Possible bug with Dell OMSA and WMI hardware polling

I believe this is an OMSA related issue so here goes. I tried searching the forums for this but I am not sure I was entering the correct terms for this issue.

I am in the process of starting to use SolarWinds Orion platform to monitor our servers via WMI and came across this strange issue. After configuring a particular server in SolarWinds, I can see it showing data for everything except the hardware polling where it displays this error:

Access denied Scope: w.x.y.z\root\cimv2\dell[\domain\account] ErrorCode: 0x80041003

I set it up this way: Solarwinds [hereafter SW] monitoring account is a AD domain user. The account is a member of a AD domain global security group. This group is a member of the local administrators group on all the servers so through this mechanism, the monitoring account is a local admin. And it works, I have all the permissions and rights of a local admin, except I get the error above in SW for hardware polling.

After many trial and error attempts, I found the answer. Incredibly, if I add the monitoring user as an enumerated member to the local admin group instead of relying on group membership to confer administrative permissions, it works. SW is now happy and i can see all the hardware data. I can break it again by removing the user as a direct member of the local admin group. So my question is: Why do I have to do this? Shouldn't being part of a AD security group in the local admin group of a server do the same thing? Am I missing something here? Feels like this is a bug in OMSA?

Relevant info:

Most servers are running Windows Server 2008 Enterprise, one is on Windows Server 2008 R2 Enterprise and one is running Windows Server 2003 R2, Enterprise x64.

Wbemtest [run from the SW server to target server being monitored] worked as expected when the account was getting administrative perms through group membership. I could even run successful querys against the server which makes me think this is not a WMI issue.

Servers are a mix of PE R710/720's all running the latest OMSA version [8.1.0.1 for Windows 2008, 7.3.0 for Windows 2003].